We have had several requests lately for Sirius Red.  We normally use the
Congo Red technique.  My question is:  Is there supposed to be the green
birefringence staining with the Sirius Red?  I've checked all my
resources.  It is not mentioned in the few procedures I found and one
book was contradictory.  I assume it is not supposed to since the
sections are cut thinner (at 4-6 m.), and the majority of the procedures
didn't mention it.  I just want to ask others who are more experienced
to make sure I have the facts.

We do have a polarizer and there wasn't any birefringence even though
the control had dark pink areas.

Thanks for your help.

Rita